[solved] what to choose, pipewire +jack-sdk or jack2?

[spica]

Hello everyone,

I'm facing a seemingly straightforward decision, but I'm struggling to make up my mind. I've noticed a significant shift from PulseAudio to Pipewire. While I've come across information suggesting that Pipewire can function as a Jack server, I'm unsure about the best choice for Jack clients — Jack2 or Pipewire.

I recently purchased a guitar and an external soundcard (guitar amplifier) that connects via USB 3 to my computer. I'm using Guitarix, which requires Jack to be present. I've experimented with both Jack2 and Pipewire with the jack-sdk flag enabled, and both options seem to work. I've tested them at 128/48000, and I didn't encounter any xruns. However, when I reduced it to 64/48000, I did experience a few xruns in both cases.

I'm unsure about whether I need to use other Jack-based software in the future, but as of now, it appears that Guitarix is the sole application I'll be using. It seems convenient to go with Pipewire with the jack-sdk flag enabled, as it offers a simpler setup.

However, my intuition is suggesting that using a dedicated Jack service might provide better performance, potentially resulting in shorter latencies and fewer xruns compared to the current Pipewire + jack-sdk setup.

Am I on the right track with my thinking? I just want to make an informed decision regarding which option to choose.

[Dominique_71]

For the use you want to do, a very low latency is not a requirement, which imply you can go with a jack setup that give You no xruns.

That said, the choice between jack and jack2 is obvious, jack was developed for uni-processor machines and is now in maintenance only mode. But it still works fine and is the preferred choice for such machines. Jack2 was developed from the start with multi-processors machines in mind, and it have been very stable from years.

Pipewire is another story. It was developed from the start with both audio and video in mind. Its goal is to provide for audio and video what jack provide for audio. With the development of wayland, pipewire is used now to implement some networked desktop sharing capabilities. which imply than, if you are a wayland user and want to use jack2, You must take a look at the wayland USE flags. But for me that doesn't use wayland, the main issue is than pipewire is still at a very early stage, it cannot be considered as a stable software, which imply I am not in a hurry to try it, when my current audio system based on jack2 and the jack ALSA plugin give me entire satisfaction.

To resume, if you are adventurous, pipewire is a good choice. Otherwise jack2 is the way to go on a modern multi-cores computer.

For the latency, 64/48kHz is a latency around 1.3msec, which is very low. The double, 2.6 msec is normally fully acceptable when making music. That said, You are using USB3 and must know than many latency issues with jack audio via USB can be caused by the built-in USB controller on the motherboard, and not by the soundcard. I don't know if it is possible to test that USB latency. I read reports from peoples getting a lower latency with a good PCI<->USB card into the computer. With a laptop, I don't know if such USB converters exist for their connection standards.

[spica]

Thank you. I will go the adventurous way